The global cholera situation is worsening, with outbreaks across 31 countries and a surging fatality rate, the World Health Organization said Friday.

"Given the scale, severity, and interconnected nature of these outbreaks, the risk of further spread within and between countries is considered very high," it said.

The UN health agency said the deteriorating outlook was "driven by conflict and poverty", with rural and flood-affected areas especially vulnerable to the disease -- an acute intestinal infection that spreads through food and water contaminated with bacteria, often from faeces.